Multiple boring machine



.J J cRoFT, sR 2,535,670

MULTIPLE BORING MACHINE 4 Sheets-jSheec 1 Jhn, J Croft, .511)

bte/um@ Dec. 26, 1950 Flled Feb 3, 1947 mm km Dec. 26, 1950 .1. J. cRoFT, SR 2,535,670

MULTIPLE BORING MACHINE Filed Feb. 3, 1947 4 Sheets-Sheet 21 @ma Croft, Jn,

m #MMM Dec. 26, 1950 J, J. cRoF-r, 5R 2,535,670

MULTIPLE BORING MACHINE Filed Feb. 3, 1947 4 ShetS--Sheerl 3 iml Il \z m (D I\\\\\\\\\\ WOT nl tu L A 16 "lllllL-l!! Non S11/ocmw@ Dec. 26, 1950 J. J. cRoFT, SR 2,535,670

MULTIPLEBORING MACHINE Filed Feb. 3, 1947 4 Sheets-Sheet 4 mmm Ziff/? Patented Dec. 26, 1950 UNITED STATESv PATENT OFFICE l l 2,535,670 MULTIPLE BORING MACHINE John J. cron, sr., Siler city, N. c., assignor to High Point Bending c Chair Company, Siler City, N. C., a corporation of North Carolina Application February s, 1947, serial No. 726,013

This invention relates to an automatic machine, capable of performing various different operations upon various different pieces of work of' various different materials, but more especially designed for performing boring, doweling, cutting-oli" and similar operations upon wooden elements such as legs, 'stretchers and the like from Which chairs and othel` articles of furniture are constructed, and has for its general object to provide a. simple, practical automatic machine to perform operations' `such as those mentioned and which heretofore have required the use of two or' more separate machines, thereby materially to'reduceproduction time and costs.

The' present machine comprises -a frame including -a plurality of work-head supporting bars; means for fastening a piece of work to be o`perated upon, andl a plurality of work heads mounted upon said bars for operation upon a piece of work fastened by said fastening means. Each work' head includes a motor for driving a' tool for operation upon the Work and a guide element' upon which said motor is mounted to slide to project and retract the tool relative to the work, and in this connection a special object of the' invention is to construct each work-head so' that the motor guide element, and hence the motor;V may readily be adjusted along, rotatably about and laterally" with respect to its supporting bar, as well as rotatably about an axis extending at right angles to the axis of its supporting bar, so' as' to position th'e tool in" practically any desired attitude relative to the work for operation thereon.

Suitable yieldable means tendsloo'nstantly to retract each motor;v uideo'pe'rated `cylinder and piston means is provided to project each motor, and suitable valve means is provided for controlling supply of fluid under pressure to each cylinder and piston means and its exhaust therefrom so that the' motors and the tools are projected and retracted at desired times, eitherI simultaneously' orin desired sequence, depending' upon the particularoperations being performed; In `this connection it' may bein some instances that the ,l i

`5 Claims. (Cl. D14-112) motor' has been retracted so as t'o insure against any possible interference of projection of ari-'3ia given motor with projection of any otherinotoi Another special and important object of the ifid vention is to construct the work heads coni-` pactly and, at the same time, to provide simple, practical means for effecting and maintaining" adjustments of the motor supporting guide -ele"- ments.

With the foregoing and other objects view, which will become more fully apparent as the nature of the invention is better understood, the same consists in an automatic machine embed ing the novel features of construction, combi tion and arrangement of parts as will be herey inafter more fully described, illustrated inthe) accompanying drawings and dened in the and pended claims.

In the accompanying drawings, wherein lil' characters of reference denote corresponding parts in the different views:

Fig. 1 is a front elevation of ari automatic-` ma# chine constructed in accordance with oneI practical embodiment of the invention.

Fig. 2 is a top plan view of the machine.

Fig. 3 is a cross sectional view through the nia-f chine taken appr'oximatelyon the line 3;-33 of Fig; 1.

Fig. 4 is an enlarged view, partly in side ele# vation and partly in section, of one of the Woilr heads.

Fig. 5 is a frontl elevation of the work' head shown in Fig. 4. t l

Fig'. 6 is a top plan view of the Work head shown in Fig; 4.

Fig. 7` is a view similar to Fig. 4 looking toward the opposite side of the work head.

Fig; 8 is a section on the line-iB-B of Fig. 4;

Fig. 9 (Sheet 2) is a section on' the linev 92S of Fig. 4.

Fig; 10 is" a; Section Ori the line lll-i0 'f Figi. 4; and

Fig. l1 is a detail'` view illustrating valve means` operable by projection and retraction of the motor' of one work' head to control supply of huid to the cylinder and piston projecting means of anotlie work head. l

Referring' to the drawings `in detail, A desigel nates generally the frame of the present`:machine which maybe of any suitable construction and which is illustrated in the present instance as comprising al pair of end plates IB, IU connect'edY together near their tops by a plurality of head supporting bars H and near their bottoms by plurality' cf stay cars l2 The number oi the work head supporting bars Il and their arrangement relative to each other is arbitrary. For practical purposes, however, there may be upper and lower, forwardly and rearwardly spaced apart pairs of these bars, the lower pai1` of whi-ch may be somewhat more widely spaced apart than the upper pair, as shown. In addition, either or both pairs of said bars i i may support one or more forwardly and rearwardly extending work-head supporting bars I3. The work-head suppcrting bars themselves as well as the stay bars l2 preferably are of tubular form, as shown, so as to combine lightness in weight with rigidity and strength.

The work-heads are designated generally as B and their number, as well as their disposition relative to each other and with respect to their supporting bars, is arbitrary, depending upon the particular operations to be performed.

Any suitable means may be provided for fastening a piece oi work to be operated upon by the work-heads B. Preferably, however, the work fastening means comprises duplicate units, designated generally as C, any desired number of which may be employed in any given inst-ance and which are designed to be mounted upon the upper pair of the bars il, for example, in desired spaced apart relationship to each other, depending upon the particular size and shape of a piece of work to be fastened.

Each unit C `may comprise, as shown, a bar I4 extending forwardly and rearwardly across the spacebetween the upper pair of the bars Il and provided at its ends with suitable bar l I embracing and clamping means I5 whereby it may be work-piece rest l5 which is provided with a set screw l'i for engagement with the bar I4 to secure said rest in a desired position of adjustment along said bar, while rising from said rest is a standard I8 upon which is suitably mounted for Vertical adjustment relative thereto a cylinder I9 which overlies the rest I6.

vIn the cylnder i 3 is a piston 2d having a piston rod 2l which extends through the lower end of said cylinder and which is provided at its lower end with a suitable foot piece 22 to engage the top of a piece of work a resting upon the rest I6 and to clamp it against sad rest when air or other fluid under pressure is admitted to the top of the cylinder I9 to-urge the piston 20 downwardly. Suitable spring means, such as is indicated at 23, is provided to ra'se the piston 23 and the foot piece 22 to release the work-piece a when the upper end of the cylinder I9 is relieved of iiuid pressure.

Each work head B comprises a guide element 24- upon which a motor 25 may be slidably mounted in any suitable manner for projecton and retraction to project and retract a tool 2G, driven by the motor, to and from a position to perform its operation upon a piece of work a fastened by the units C. In this connection and as illustrated in the present instance, the guide element 24 is provided at its rear side with a channel 21 (Figures 4 and 6) of dove-tail shape in cross section and the motor 25 is provided with a base 28 of dove-tail shape in cross sect'on disposed in said channel, whereby the motor is maintained operatively engaged with said guide element and yet is projectable and retractable relative thereto.

In accordance with known practice, tool heads 29 for tools of dferent kinds may be interchangeably mounted on any given motor 25 so that any such motor may be employed to drive any given tool or tools 2B, as, for example, a circular cutoi saw, a dowel-forming chuck, or one or more drills or bits.

For projecting the motor 25 and its tool, a cylinder and piston unit 30 comprising a cylinder 3l and a piston 32 is employed. -The cylinder 3l is mounted on the guide element 24 behind the motor 25 and the piston 32 has extending therefrom a piston rod 33 which is engaged with the rear end of the motor. Consequently, by admitting air or other uid under pressure to the rear end of the cylinder 3l, the piston and the piston rod are moved to project the motor. On the other hand, suitable spring means, as indicated at 34, is provided to retract the motor and to hold it retracted whenever the rear end of the cylinder 3| is relieved of fluid pressure.

The cylinder and piston unit 30 constitutes a stop to limitretractive movement of the motor 25, and since the motor always is projected the same amount when iiuid pressure is` admitted to the rear end of the cylinder 3l, it is desirable to provide for adjustment of said cylinder and piston unit longitudinally relative to the guide element 24 to variably predeterminethe retracted position of the motor 25 relative to said guide element to adapt the-tool driven by the motor to be projected the proper amount relative to any'v given piece of work fastened by the work fas-l tening units B. To this end the cylinder 3l may be provided with a base 35 of dove-tail shape in cross section engaged in the channel 21 of the guide element 24 to slidably mount said'cylinder on said guide element, and said guide element may carry a screw 36 swiveled with respect thereto and in threaded engagement with said base 35 so that by rotating said screw the cylinder and piston unit 30 may be adjusted to any desired position longitudinally with respect to said guide element 24.

Rigid with the guide element 24 and extending forwardly therefrom at right angles thereto is an arm 31 of cylindrical shape in cross section which fits neatly within a cylindrical bore 38 in a housing 39 carried rigidly by a bracket 40.

The bracket 4G is composed of half sectionsl 4l and 42 which embrace the supporting bar ll upon which the work head is mounted, andsaid half sections are hinged together at one side of the bracket, as indicated at 43, and are con-` nected together at the other side of the bracket by a clamp screw 44, whereby they may be released to permit rotative and longitudinal adjustments of the bracket relative to the supporting barl il and may be drawn together to clamp the bracket upon said bar in any desired position of adjustment of the bracket along and ro-l tatively with respect to said bar.. f

The housing 39 extends at right angles to the` bar Il and has swiveled in the front end ythereof a Screw 45 which extends axially relative to said housing and is in threaded engagement with the' arm 31. Accordingly, by rotatably adjusting-'said screw 45, the arm 31 and, consequently, the guide element 24 may-be adjusted laterally relative to the supporting bar ll.

On the arm 31 and keyed thereto, as indicated at 46, is a worm wheel 41 which is housed -b'ythe bracket 4l)I and which has engaged there,- with a worm 48 which is suitably mounted said bracket. Accordingly, by rotating Y said andere worm, said'. worm. wheel. may," be rotated" tot rotatably` adjust the` arm 3T and the guide element iw` carried thereby..

t portiorr` of the housing 40 is' formed: asa tongue Mlfof` limited circumferential extenthaving, aa free` end 5i! through which a clampscrew 51|` extends loosely andY is threaded into the bracket 49. This clamp screw is loosenedwhenever" it is desired to rotatably or longitudinally adjust the arm 31 and is tightened to draw the tongue 49 into clamping engagement with said arm to maintain the latter in anyl position to which` it may be` adjusted.

Keyedi on the supporting barl l1', as indicated at 52 whereby it may slide longitudinally but is held) against rotation, relative to said bar, is a worm., wheel rwhich` has a swiveled connection withuthe bracketd, as indicated at 54,.whereby said brachetxmay rotate relative to: said:r worm wheeltbut is constrained to` move therewith longitudinally along thebar il.`

Carried by the bracketll is a worm` 55 which meshes with the worm wheel 53. Accordingly, byf rotatably adjusting said worm 55, the bracket dfmay' be adjusted rotatably about the supporting; bar il to adjust the guide element Zitto any desired angle between the vertical andthe horizontal. l

The supporting arm Il is provided with rack teeth: t and the worin wheel 53* has: journaled thereinaa' shaft 5l on: which is fixed a; pinion 58 which` is in mesh with said racl; teeth. Accordingly, by rotating said shaft 5l and its pinion 58,' the entire unit B maybe adjusted longitudinally along the,` supporting bar ii; The olampscrewflfi is',` ofcourse; loosened whenever itis desired to rotatably or longitudinally adjust the bracketliil and'. the parts" carried'thereby, and may be tight#- ened to maintain any adjustments made;

The toolY drivingmotors may be eitherelectrc motors or motors that are driven by air or other fluid under pressure, or some of them may be electric' motors and others may be fluid driven motors. Moreover, instead ofthe specific means described for effecting adjustments of the motor- A carrying guide elements and the motors, any other suitable means for this purpose may be provided; As illustrative, Figs. l, 2 and 3 ofthe drawings show one of the work head units, designated as B', as being equipped with an airdriven motor designated as Q5". These iigures further illustrate a simple clamp bracket 59 in which the arm 31 of the guide element 2li of said unit B1 is: rotatably and longitudinally adjustable, and another simple clamp bracket @3' by which the clamp bracket es. is carried and by means of which the unit B is mounted on its supporting bar I I for adjustments `longitudinally therealong` and` rotativelywith resp-ect thereto.

In Figs.` 1, 2 and Brthe machine is illustrated as being set up for` boring all necessary holes in a chair leg prior to its assembly with other elements to make up a chair. Any suitable means may be employed to insure proper positioning of ,the chair leg relative to the fastening units C before it: is clamped bysaid units, and the work heads. are", of course, properly adjusted so that when,` their motors and tools are projected the desired holes will be bored'in the leg at the proper locations. One of the work heads is illustrated es being'mountedupon the rear of the lower pair of supporting? bars li. for forward .projection of its motor toY bore a hole in the front edge of the chair leg; four of the wo e heads. are illustrated aslrbeiirgrmounted: upon the front of the lower pair off ther supporting bars, H forupwardi pro:- jection-of their motors: toA bore holes in thelside or: the.: chair: leg, and another: of thei work. heads (the work head B) isiillustratedasbeing mount-- ed upornthezfront: of the upper pair oft supportingrbenfs'A Hr forl rearward projection'. ofz its motor to: bore ahole in the rear edge of the chair leg; lvvcr` other work:` heads also are illustrated, one asl being mounted upon.. a. transverse supporting bar' LSLatone end of` the machine and provided withatoolrin the formoi adowel-forming chuck, and; the otherI also as being mounted upon. a transverse supporting bar; at the. other end', of the machine: and as' being` provided with a` tool in the,V form of a circular cut-oi saw.. These two last mentioned units are not :employed to` per.- iorm any operationsonthechair leg a, but are illustrated merelyto'ashow that they maybe: em;- ployed to performdowel`-forming and cut-off op,- erations upon the ends of' other pieces of,` work clamped by thework fastening units C.A Obvious.- ly;` two of' thev units provided with cut-od saws may be employed, one at each: end of the machine or;` alternatively, twozof the unitsjprovided with dowel-formingchucksmay be employed, one' als-eachV end oif the machine. In fact, any desired combination and arrangement of the work heads may be` employed to perform all*4 required operations on any given piece of. worlr` clamped by the work` fastening units C.

When` thel machine is set up for performing all required' operations upon pieces of work all of which are. alike, all of` the various different tool driving motors are connected toV a source of' electric current or' to a source of air or other operating iluid under pressure and are =continuously operated. On the other hand, the motors may be projected simultaneously or in desired sequence depending upon whether all are free tobe projected simultaneously or whether'projection of any` one might interfere with projection of any other" of the same. To insure projectionA of the motors as well as projection of the work clamping elements at the proper times, a Suitable valve, designated generally as ed, driven by an' electric motor d! or by any othersuitable means,.may be interposed between the source of' fluid under pressure, represented by the pipe 52, and the hose or. otherconduits leading to the different motor and tool' projecting and work clamping cylinders. TheV valve Elliand its driving motor i may conveniently be mounted upon a platform 54 at: the upper, rearpart of the machine supported upon suitable bracket arms 55 mounted upon the end plates i t, Iii' ofthe machine, and the driving connection` between said valve (iii and said motor 6! may include a suitable speed reduction unitA 66' whereby said valve" is driven at a suitable Ylow speed The valve 6D may have, for example, three outlets, as shown, each connected to a separate manifold pipe El', and the construction of said valve may besuch that as it is driven it directs air or other fluid under pressure to `the, manifold pipes 6l' successively. Any cylinder and piston units thatare to be simultaneously operated may be connected to oneof'said manifold pipes, while any cylinder and piston units that are to be operated at different times may be connected to different of said manifold pipes. Thus,` the 'worku clamping cylinder and piston units may be connected to oneV manifold 'pipe- 6'.' for op'- eration in advance of' the cylinder vandv piston units for advancing the tool driving motors; and

the latter cylinder and piston units may be connected to the other of said manifold pipes for operation simultaneously or in proper sec uence, as may be necessary.

When the machine is in operation all of the tool driving motors are, as aforesaid, driven continuously and the work clamping and the tool driving motors are advanced and retracted at proper and regular intervals. First, the work clamping units are actuated to clamp a piece of work a to be operated upon; next the different tool driving motors are advanced either simultaneously or in desired sequence to cause their tools to perform their operations and then are retracted and remain retracted until the work clamping units are released. The piece of work a operated upon then is removed and a new piece of work is positioned to be clamped and operated upon, whereupon the clamping and work performing operations are repeated, all automatically. The speed of operation of the valve t@ may be varied in any suitable manner to vary the Aspeed of operation of the machine which is, in turn, dependent upon the rapidity with which any given operator of the machine may supply and remove work pieces a to and from the work clamping units C.

Preferably the work-piece rests iii are provided with suitable arms d8 to guide the workpieces cy during their supply to and removal from the machine so as to avoid the possibility of their contacting with and becoming marred by any given tool located in front of the work clamping means.

Each manifold pipe 6l may have as many outlet nipples $9 as desired with which may be connected by hose 63 to any desired cylinder and piston units, and said nipples may have normally closed valves to be opened by connection of the hose with the nipples in accordance with known practice so that air or other fluid is delivered through only those nipples with which hose are connected.

Conveniently, a panel it may be provided in front of the platform 54 to support one or more of lthe manifold pipes Si and to have the nipples 69 extend therethrough for ready connection of hose therewith as well as to support electrical outlets li with which the cables 'l2 leading to the tool operating motors may be connected.

In any instance where a given motor or its tool is projected across the path of projection of another motor or its tool, means may be provided to insure against projection of the rst mentioned motor and its tool unless the second mentioned motor and its tool are retracted, thereby to insure against collision and damage of the respective work heads. This means may comprise a normally closed valve i3 interposed in the hose leading to the cylinder and piston projection unit B of the irst mentioned motor and mounted so as to be opened by retraction of the second mentioned motor. Thus, operating iiuid cannot flow to the cylinder and piston unit of the rstmentioned motor unless the second men tioned motor is retracted. 1l of the drawings illustrates the valve as being mounted upon the cylinder of a motor projecting unit and as having a stem M to be engaged by the motor when the latter is retracted for the purpose of opening said valve. The valve itself may be of any suitable construction such that it closes when the motor is projected and is opened responsiveto depression of its stem 'is by the motorZ From theV foregoing description 'considered in connection with the accompanying drawings, it is believed that the construction and operation of the machine will be clearly understood and its advantages appreciated. It is desired to point out, however, that While only a single, specific structural embodiment of the invention has been illustrated and described, the same is readily capable of embodiment in specically different structures within its spirit and scope as defined in the appended claims.

What is claimed is:

1. A machine of the character described comprising a frame including a rack bar, work fastening means, a gear wheel mounted on said rack bar for sliding adjustments therealong and nonrotation relative thereto, a bracket swiveled to said gear wheel for sliding movement therewith and for rotation relative thereto about the axis of said rack bar, a pinion mounted on said gear wheel and in mesh with the rack of said rack bar for slidably adjusting said gear Wheel and said bracket relative to said rack bar; a second gear wheel carried by said bracket and in mesh with said rst mentioned gear wheel for rotative- 1y adjusting said bracket relative to said first mentioned gear wheel and said rack bar, a guide element mounted on said bracket for adjustment toward and away from the same, a motor mounted on said guide element for projection and retraction relative thereto, and a tool driven by said motor for operation upon a piece of work fastened by said work fastening means. f

2. A machine of the character described comprising a frame including a rack bar, work fastening means, a gear wheel mounted on said rack bar for sliding adjustments therealong and nonrotation relative thereto, a bracket swiveled to said gear wheel for sliding movement therewith and for rotation relative thereto about the axis of said rack bar, a pinion mounted on said gear wheel and in mesh with the rack of said rack bar for slidably adjusting said gear wheel and said bracket relative to said rack bar; a second y gear wheel carried by said bracket and in mesh with said lirst mentioned gear wheel for rotatively adjusting said bracket relative to said first mentioned gear wheel and said rack bar, a guide element mounted on said bracket for rotative adjustments about an axis at right angles to the axis of said rack bar and also for adjustments toward and away from said bracket and said rack bar, a motor vmounted on said guide element for projection and retraction relative thereto, and a tool driven by said motor for operation upon a piece of work fastened by said work` fastening means.

3. A machine of the character described comprising a frame including a supporting bar, work fastening means, a bracket mounted on said supporting bar for adjustments longitudinally and rotatively relative thereto, said bracket including a housing extending at right angles to said supporting bar, a guide element, an arm rigid with said guide ele-ment and mounted in said housing for adjustments longitudinally and rotatvely relative thereto, a gear wheel on said arm and keyed thereto and mounted for rotation but non"- longitudinal movement relative to said bracket, a second gear wheel carried by said bracket and meshing with said first mentioned gear Wheel for rotatively adjusting said arm and guide mem; ber relative to said bracket, a motorimountedon 4said guide element for projection and retraction relative thereto, and a tool driven by said motor for operation upon a piece of work fastened by said Work fastening means.

4. A machine of the character described com.- prising a frame including a supporting bar, work fastening means, a bracket mounted on said supporting bar for adjustments longitudinally and rotatively relative thereto, said bracket including a housing extending at right angles to said supporting bar, a guide element, an arm rigid with said guide element and mounted in said housing for adjustments longitudinally and rotatively relative thereto, a gear Wheel on said arm and keyed thereto and mounted for rotation but non-longitudinal movement relative to said bracket, a second gear Wheel carried by said bracket and meshing with said rst mentioned gear wheel for rotatively adjusting said arm and guide member relative to said bracket, screw means for adjusting said arm longitudinally relative to said housing, a motor mounted on said guide element for projection and retraction relative thereto, and a tool driven by said motor for operation upon a piece of work fastened by said Work fastening means.

5. In a machine of the character described, Work fastening means, a first projectable and retractable motor, a second projectable and retractable motor, a tool driven by each motor for operation upon a piece of work fastened by said Work fastening means, yieldable means tending constantly to retract each motor and its tool, a fluid-operated cylinder and piston unit for projecting each motor and its tool, the path of projection and retraction of one of said tools being disposed in the path of projection and retraction of the other of said tools, fluid pressure supply conduits connected to said cylinder and piston units, and means to insure retraction of said rst mentioned tool and its driving motor before said second mentioned tool and its driving motor may be projected, thereby to avoid collision and damage of said tools or motors, said last named means comprising a normally closed Valve in the fluid pressure supply conduit of the second mentioned cylinder and piston unit mounted to be opened only by contact on retraction of said first mentioned motor with the stem of said valve.

JOHN J. CROF'I, SR.

REFERENCES- CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 895,093 Knight Aug. 4, 1908 1,422,971 Hanson July 18, 1922 1,748,556 McKnight Feb. 25, 1930 1,858,677 McKnight 1 May 17, 1932 1,860,700 Bauch May 31, 1932 1,973,204 Gross et al Sept. 11, 1934 2,022,288 Knapp Nov. 26, 1935 2,047,603 Tremblay July 14, 1936 2,133,613 Gardner Oct. 18, 1938 2,258,828 Trebert Oct. 14, 1941 FOREIGN PATENTS Number Country Date 493,004 Germany Mar. 3,1930 

